Adhesive composition components, such as base polymers, tackifiers, and waxes are customarily provided as separate components for formulation into an adhesive composition. For hot melt adhesive (HMA) application systems, the base polymer is often supplied in the form of solid pellets, which may be melted and combined with the other adhesive components.
In HMA applications, improved adhesive compositions are sought that provide a desired combination of physical properties, such as reduced set time and improved mechanical strength. In some instances, individual polyolefins having certain characteristics have been blended together in the hopes of combining the positive attributes of the components. Typically, however, the result is a blend that displays a weighted average of the individual properties of the individual resins.
Although many polymers have been discovered that possess new and interesting properties, many potentially advantageous polymers have not been employed in adhesive compositions or otherwise explored for a myriad of reasons, including apparent processibility limitations. For example, some polymers may be difficult to process because of the apparent impracticability of pelletizing the polymer at commercial processing speeds. Some polymers, particularly those having an exceptionally low heat of fusion, may pass too readily through a pelletizer without forming well-defined pellets. Other polymers, particularly those having an exceptionally high heat of fusion, may not tolerate standard process condition variability (e.g., temperature variations) and as a result may plug the die plate.